[moderation] [bluetooth?] KCSAN: data-race in l2cap_chan_connect / l2cap_sock_bind

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 32f88d65f01b Merge tag 'linux_kselftest-fixes-6.10-rc3' of..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13b26e16980000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c00b51a1d411353
dashboard link: https://syzkaller.appspot.com/bug?extid=a6d6de7973ae8920f5ce
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [johan....@gmail.com linux-b...@vger.kernel.org linux-...@vger.kernel.org luiz....@gmail.com mar...@holtmann.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7b9118c037fa/disk-32f88d65.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3b902fb6c147/vmlinux-32f88d65.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cafa3499b56c/bzImage-32f88d65.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a6d6de...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in l2cap_chan_connect / l2cap_sock_bind

write to 0xffff88811c45f41e of 1 bytes by task 17884 on cpu 1:
l2cap_sock_bind+0x30e/0x520 net/bluetooth/l2cap_sock.c:133
__sys_bind+0x15b/0x1d0 net/socket.c:1847
__do_sys_bind net/socket.c:1858 [inline]
__se_sys_bind net/socket.c:1856 [inline]
__x64_sys_bind+0x41/0x50 net/socket.c:1856
x64_sys_call+0x25b5/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:50
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811c45f41e of 1 bytes by task 17885 on cpu 0:
l2cap_chan_connect+0x4c/0x980 net/bluetooth/l2cap_core.c:6960
l2cap_sock_connect+0x3c4/0x450 net/bluetooth/l2cap_sock.c:256
__sys_connect_file net/socket.c:2049 [inline]
__sys_connect+0x1a9/0x1c0 net/socket.c:2066
__do_sys_connect net/socket.c:2076 [inline]
__se_sys_connect net/socket.c:2073 [inline]
__x64_sys_connect+0x41/0x50 net/socket.c:2073
x64_sys_call+0x2961/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:43
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17885 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00022-g32f88d65f01b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
==================================================================


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